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Details of the OPTEX Procedure 
See OPTEX4 in the SAS/QC Sample Library 
An automotive engineer wants to fit a quadratic model to fuel consumption data in order to find the values of the control variables that minimize fuel consumption (refer to Vance 1986). The three control variables and their possible settings are shown in the following table:
Variable  Values  
AF  15  16  17  18  
EGR  0.020  0.177  0.377  0.566  0.921  1.117  
SA  10  16  22  28  34  40  46  52 
Rather than run all 192 (4×6×8) combinations of these factors, the engineer would like to see whether the total number of runs can be reduced to 50 in an optimal fashion.
Since the factors have different numbers of levels, you can use the PLAN procedure (refer to the SAS/STAT User's Guide) to generate the full factorial set to serve as a candidate data set for the OPTEX procedure.
proc plan; factors af=4 ordered egr=6 ordered sa=8 ordered / noprint; output out=a af nvals=(15,16,17,18) egr nvals=(.020,.177,.377,.566,.921,1.117) sa nvals=(10,16,22,28,34,40,46,52); run;
The DETMAX algorithm of Mitchell (1974a) is very commonly used for computergenerated optimal design. Although it is not the default search method for the OPTEX procedure, you can specify that it be used with the METHOD=DETMAX option in the GENERATE statement. For example, the following statements produce Output 24.2.1.
proc optex data=a seed=61552; model afegrsa@2 af*af egr*egr sa*sa; generate n=50 method=detmax; run;Output 24.2.1: Efficiencies with DETMAX Algorithm
proc optex data=a seed=33805; model afegrsa@2 af*af egr*egr sa*sa; generate n=50 method=sequential; run;Output 24.2.2: Efficiencies with Sequential Algorithm

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